systemMonitorTask = TimeoutManager.getInstance().addTimeoutTarget(new SystemMonitorTarget(),
                    ComponentUtil.getFessConfig().getThumbnailSystemMonitorIntervalAsInteger(), true);

            final int totalCount = process(options);
            if (totalCount != 0) {
                logger.info("Created {} thumbnail files.", totalCount);
            } else {

     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     * @throws NumberFormatException When the property is not integer.
     */
    Integer getThumbnailSystemMonitorIntervalAsInteger();

    /**
     * Get the value for the key 'user.code.request.parameter'. <br>
     * The value is, e.g. userCode <br>
     * comment: user